Add persist method (#367)

addon/-sdk/context.js

@@ -1,7 +1,18 @@
 import { isNone } from '@ember/utils';
 import { TrackedMap } from 'tracked-maps-and-sets';
 
+const STORAGE_KEY = 'ember-launch-darkly';
+
+function setPersistedFlags(context) {
+  let persistedFlags = window.localStorage.getItem(STORAGE_KEY);
+
+  if (persistedFlags) {
+    context.replaceFlags(JSON.parse(persistedFlags));
+  }
+}
+
 function setCurrentContext(context) {
+  setPersistedFlags(context);
   window.__LD__ = context;
 }
 
@@ -62,6 +73,14 @@ class Context {
     return this._flags.get(key);
   }
 
+  persist() {
+    window.localStorage.setItem(STORAGE_KEY, JSON.stringify(this.allFlags));
+  }
+
+  resetPersistence() {
+    window.localStorage.removeItem(STORAGE_KEY);
+  }
+
   get allFlags() {
     let allFlags = {};
 
@@ -76,6 +95,11 @@ class Context {
     return isNone(this.client);
   }
 
+  get persisted() {
+    let persisted = window.localStorage.getItem(STORAGE_KEY);
+    return persisted ? JSON.parse(persisted) : undefined;
+  }
+
   get client() {
     return this._client;
   }
@@ -93,5 +117,6 @@ export {
   getCurrentContext,
   removeCurrentContext,
   setCurrentContext,
+  setPersistedFlags,
   Context as default,
 };

tests/unit/-sdk/context-test.js

@@ -1,6 +1,6 @@
 import { module, test } from 'qunit';
 
-import Context from 'ember-launch-darkly/-sdk/context';
+import Context, { setPersistedFlags } from 'ember-launch-darkly/-sdk/context';
 
 module('Unit | SDK | Context', function () {
   test('constructor', function (assert) {
@@ -156,4 +156,36 @@ module('Unit | SDK | Context', function () {
     });
     assert.deepEqual(new Context({}, client).user, { key: 'foo' });
   });
+
+  module('#persistence', function (innerHooks) {
+    innerHooks.afterEach(function () {
+      window.localStorage.removeItem('ember-launch-darkly');
+    });
+
+    test('#persist / persisted', function (assert) {
+      let context = new Context({ foo: true, bar: false });
+      context.persist();
+
+      assert.deepEqual(
+        context.persisted,
+        { foo: true, bar: false },
+        'Flags persisted in local storage'
+      );
+    });
+
+    test('#setPersistedFlags', function (assert) {
+      window.localStorage.setItem(
+        'ember-launch-darkly',
+        JSON.stringify({ foo: true, bar: false })
+      );
+      let context = new Context({ foo: false, bar: true });
+      setPersistedFlags(context);
+
+      assert.deepEqual(
+        context.allFlags,
+        { foo: true, bar: false },
+        'Persisted flags were set to context'
+      );
+    });
+  });
 });